析構函數被多次調用並且不合適

Question

ma模型類中的問題是處理它組成的每個網格。當它由7個網格組成時，首先析構函數被調用21次。在退出程序後，它被稱爲14次。真的不知道我做錯了什麼。我能夠將問題轉化爲這種特殊的代碼。

void Model::processNode(aiNode *node, const aiScene *scene) { 
    for(unsigned int i = 0; i < node->mNumMeshes; i++) { 
     aiMesh* mesh = scene->mMeshes[node->mMeshes[i]]; 
     mMeshes.push_back(processMesh(mesh, scene)); 
    } 
    for(unsigned int i = 0; i < node->mNumChildren; i++) { 
     processNode(node->mChildren[i], scene); 
    } 
} 

mMeshes是單個模型對象的網格的私有向量。

編輯：

爲了澄清，問題是，當網格類的析構函數沒有被註釋掉，它完全破壞了mMeshes矢量一切。這是Mesh的析構函數

Mesh::~Mesh() { 
    glDeleteVertexArrays(1, &mVAO); 
    glDeleteBuffers(NUM_BUFFERS, mVBOs); 
} 

這是Meshes的向量。

std::vector<Vertex> mVertices; 

和processNode的頭部，它只是創建新的網格並將其返回給向量。

Mesh Model::processMesh(aiMesh *mesh, const aiScene *scene); 

Answer 1

如果未在以適應新的元件然後在添加新元素的載體可以重新分配存儲器中的向量保留足夠的內存。在這種情況下，它分配一個新的內存擴展並將舊內存範圍內的所有元素複製到新內存。因此，將元素複製到新位置後，舊位置中的元素將被刪除。此外，成員函數push_back可以處理將被複制到矢量的臨時對象，並在此之後被刪除。

這裏是一個示範項目

#include <iostream> 
#include <vector> 
#include <string> 

struct A 
{ 
    std::string s; 
    A(const std::string &s) : s(s) 
    { 
     std::cout << "Object " << this->s << " is created" << std::endl; 
    } 

    A(const A &a) : s("copy of " + a.s) 
    { 
     std::cout << "A " << this->s << " is created" << std::endl; 
    } 

    ~A() 
    { 
     std::cout << "Object " << s << " is deleted" << std::endl; 
    } 
}; 

int main() 
{ 
    { 
     std::vector<A> v; 

     v.push_back(A("A")); 
     v.push_back(A("B")); 
     v.push_back(A("C")); 
    } 
} 

它的輸出可能看起來像

Object A is created 
A copy of A is created 
Object A is deleted 
Object B is created 
A copy of copy of A is created 
Object copy of A is deleted 
A copy of B is created 
Object B is deleted 
Object C is created 
A copy of copy of copy of A is created 
A copy of copy of B is created 
Object copy of copy of A is deleted 
Object copy of B is deleted 
A copy of C is created 
Object C is deleted 
Object copy of copy of copy of A is deleted 
Object copy of copy of B is deleted 
Object copy of C is deleted